diff --git a/PV_Forecast/module.html b/PV_Forecast/module.html
index 830de33..47bbe5c 100644
--- a/PV_Forecast/module.html
+++ b/PV_Forecast/module.html
@@ -3,7 +3,10 @@
 <head>
   <meta charset="utf-8">
   <title>PV_Forecast</title>
+
+  <!-- Externes Script: kann je nach CSP/Mixed-Content blockiert sein -->
   <script src="https://code.highcharts.com/highcharts.js"></script>
+
   <style>
     body { font-family: sans-serif; margin: 0; padding: 12px; }
     #chart { height: 420px; width: 100%; }
@@ -21,14 +24,36 @@
   <div id="chart"></div>
 
   <script>
-    const instanceId = {INSTANCE_ID};
-    const endpoint = `/hook/solcastcompare?instance=${instanceId}&action=data`;
+    const metaEl = document.getElementById("meta");
+
+    // JS-Fehler sichtbar machen (sonst: schwarze Seite, keine Ahnung warum)
+    window.onerror = function (msg, url, line, col) {
+      metaEl.textContent = `JS-Fehler: ${msg} (${line}:${col})`;
+    };
+
+    // Symcon ersetzt {{INSTANCE_ID}} mit einer ZAHL (z.B. 12345)
+    const instanceId = Number("{{INSTANCE_ID}}");
+
+
+    if (!Number.isFinite(instanceId) || instanceId <= 0) {
+      metaEl.textContent = "Fehler: INSTANCE_ID wurde nicht korrekt eingesetzt.";
+      throw new Error("Invalid INSTANCE_ID");
+    }
+
+    // Absoluter Endpoint (robuster als nur /hook/..., vor allem bei Proxies)
+    const endpoint =
+      `${location.protocol}//${location.host}` +
+      `/hook/solcastcompare?instance=${instanceId}&action=data`;
 
     let chart;
 
     async function loadData() {
+      metaEl.textContent = "Lade Daten…";
       const r = await fetch(endpoint, { cache: "no-store" });
-      if (!r.ok) throw new Error("HTTP " + r.status);
+      if (!r.ok) {
+        const text = await r.text().catch(() => "");
+        throw new Error(`HTTP ${r.status} ${text ? "- " + text : ""}`.trim());
+      }
       return await r.json();
     }
 
@@ -37,10 +62,15 @@
         ? new Date(data.meta.forecast_cached_at * 1000).toLocaleString()
         : "unbekannt";
 
-      document.getElementById("meta").textContent = `Forecast Cache: ${cachedAt}`;
-
       const forecast = data?.series?.forecast ?? [];
-      const actual = data?.series?.actual ?? [];
+      const actual   = data?.series?.actual ?? [];
+
+      metaEl.textContent = `Forecast Cache: ${cachedAt} | Forecast: ${forecast.length} | Ist: ${actual.length}`;
+
+      if (typeof Highcharts === "undefined") {
+        metaEl.textContent = "Fehler: Highcharts konnte nicht geladen werden (CSP/Mixed Content/CDN).";
+        return;
+      }
 
       if (!chart) {
         chart = Highcharts.chart("chart", {
@@ -66,7 +96,7 @@
         const data = await loadData();
         render(data);
       } catch (e) {
-        document.getElementById("meta").textContent = "Fehler beim Laden: " + e.message;
+        metaEl.textContent = "Fehler beim Laden: " + (e?.message ?? e);
       }
     }
 
diff --git a/PV_Forecast/module.php b/PV_Forecast/module.php
index 4a0e0e2..a2ad504 100644
--- a/PV_Forecast/module.php
+++ b/PV_Forecast/module.php
@@ -26,6 +26,9 @@ class PV_Forecast  extends IPSModule
 
         $mins = max(1, (int)$this->ReadPropertyInteger("RefreshMinutes"));
         $this->SetTimerInterval("UpdateForecastTimer", $mins * 60 * 1000);
+
+        // Hook registrieren (hier ist es zuverlässig)
+        $this->RegisterHook("/hook/solcastcompare");
     }
 
     public function RequestAction($Ident, $Value)
